ABSTRACT
The early 1900s was a time when it became increasingly clear that our everyday reality is only a small and limited part of everything that exists. The new descriptions of the world were so different that physics before Planck, Einstein, and Bohr is called classical physics, while everything based on quantum physics or relativity is called modern physics. Quantum physics was born out of attempts to understand how the smallest elements of matter interact with each other. It began with Max Planck around 1900 studying how the color and intensity of light from glowing bodies changed with temperature. During the 1920s, mathematical models were developed to describe how the interactions between electrons and photons worked. Waves and particles are two completely different phenomena in our conceptual world, but not in the quantum physical world.
